Speed of animation with matplotlib.animation

[ast]

Hello

I noticed that the speed of animations made
with module matplotlib.animation always seems
wrong.

Here is a small example for demonstration purpose:


import numpy as np
import matplotlib.pyplot as plt
import matplotlib.animation as animation

fig = plt.figure()
ax = fig.add_subplot(111)
txt = ax.text(0.5, 0.5, "", transform=ax.transAxes)

dt = 0.1  # 100 ms

def animate(i):
     txt.set_text("time= %.1f" % (i*dt))
     return txt,


ani = animation.FuncAnimation(fig=fig,
                               func=animate,
                               frames = 200,
                               interval = dt,
                               blit = True,
                               repeat=False)

plt.show()

----------------------
so function animate is ran every interval=dt=100ms
with i=0, 1, 2, ..., 200 and it simply prints time
(i*dt) on the figure.

The animation should last 20s, but on my computer
it is twice faster

A link to FuncAnimation doc: https://bit.ly/2t5UKjA

interval : number, optional

     Delay between frames in milliseconds. Defaults to 200.


What's wrong ?